The 20-minute workout routine to get hard 'core' abs

Get a ripped midsection—fast—with this challenging four-day program.

Workout I

Exercise 1: Bicycle Crunch

Lie on your back, extending one leg, while bringing the opposite knee toward your chest. With your hands behind your head, touch your opposite elbow to the close knee. Twist your body and touch the other elbow to your other knee.

Exercise 2: Hanging Leg Raise

Sets: 3 Reps: 12 each side

Grab onto a pullup bar and hang with your back straight. Then, raise your legs up as high as you can, rounding your lower back. If that’s too hard, raise them only to waist level.

Exercise 3: Back Extension

Sets: 3 Reps: 12

Hold a weight against your chest and lock your legs into a back-extension apparatus. Allow your torso to bend forward until you begin to lose the arch in your lower back, but no farther. Extend your back so that your body forms a straight line. Do not arch excessively.

Workout II

Exercise 1: Barbell Rollout

Sets: 3 Reps: 12

Load lightweight plates on a barbell and set it on the floor. Hold the bar with both hands about shoulder-width apart and kneel on the floor so the bar is in front of your chest. Keeping your abs braced, roll forward as far as you can until you feel your lower back is about to start sagging. Flex your lats hard and drive back to the starting position.

Exercise 2: Cable Wood Chop

Sets: 3 Reps: 12 on each side

Attach a rope handle to the low pulley of a cable station and back up far enough away from the machine so that there is tension on the cable. Stand with your feet shoulder-width apart and split your legs, so that one foot is a few feet in front of the other. Rotate your torso diagonally upward until you’re reaching overhead, in a chopping motion. Complete your reps and then repeat on the opposite side.

Load lightweight plates on a barbell and set it on the floor. Hold the bar with both hands about shoulder-width apart and kneel on the floor so the bar is in front of your chest. Keeping your abs braced, roll forward as far as you can until you feel your lower back is about to start sagging. Flex your lats hard and drive back to the starting position.

Exercise 3: Dumbbell Romanian Deadlift

Sets: 3 Reps: 20

Hold the dumbbells in front of your thighs with your palms facing you. Bend your hips and then your knees while maintaining the natural arch in your lower back. Lower your torso until you feel you’re about to lose the arch in your lower back. Keep the weights close to your body at all times.

Workout III

Exercise 1: Plank Mountain Climber

Get into pushup position and lower your elbows to the floor so your forearms are flat. Draw one knee up to your elbow, and then drive it back quickly, pulling the other knee up to the opposite elbow.

Exercise 2: Cable Wood Chop

Sets: 3 Reps: 12 on each side

Attach a rope handle to the low pulley of a cable station and back up far enough away from the machine so that there is tension on the cable. Stand with your feet shoulder-width apart and split your legs, so that one foot is a few feet in front of the other. Rotate your torso diagonally upward until you’re reaching overhead, in a chopping motion. Complete your reps and then repeat on the opposite side.

Exercise 3: Dumbbell Russian Twist

Sets: 3 Reps: 20 on each side

Grab a medicine ball, dumbbell, or weight plate and sit on the floor with your feet raised slightly above the floor. Hold the weight straight out in front of you and keep your back straight (your torso should be about 45 degrees from the floor). Explosively twist your torso as far as you can to the right, and then the left.

Workout IV

Exercise 1: Renegade Row

Sets: 3 Reps: 12 on each side

Hold a dumbbell (or kettlebell) in each hand and get into pushup position. Shift your weight to your left side while staying rigid. Row the right-hand dumbbell to your side, but keep your torso parallel to the ground. Lower the dumbbell back to the floor, shift to the right, and row with your left arm.

Exercise 2: Decline Situp

Sets: 3 Reps: 12

Set an adjustable bench to a decline and lie back on it, securing your legs in the braces. Squeeze your abs and raise your torso off the bench until you’re sitting upright.